Method for delivery of cementitious materials and waste removal thereof

ABSTRACT

A method of delivering a necessary amount of a component for a cementitious product to a construction site, depositing the component into a container, using the component to make the cementitious product, and then retaining residual component and material resulting from rinsing the mixing equipment. In its preferred embodiment, an empty plastic container is delivered to the site, the deliverable component is sand, and the cementitious product is stucco. The amount of sand that is needed for stucco is determined and delivered to the plastic container via conveyor belts from sand trucks sitting in the street. The sand is used to mix the stucco in mixers present at the construction site, as known in the art. Once the stucco is mixed, the mixing equipment is rinsed with water and the washout effluent is deposited in the now-empty plastic container. The plastic container is then sealed and picked up with a crane sitting in the street and emptied at an accepted waste facility.

FIELD OF INVENTION

This invention relates generally to method for material handling. This invention relates particularly to a method for delivering and removing cementitious materials using the same container.

BACKGROUND

Concrete is a mixture of, among other things, sand, cement and water. Residential and commercial construction sites often use a high volume of concrete and mix it on site, or have a cement truck deliver it pre-mixed. Both methods create waste on the site that is harmful to the environment and must be removed before the buildings can be occupied. Many cementitious products other than concrete are used in construction as well, such as stucco, mortar, and pool plaster. These, too, create waste that must be disposed of properly.

For many projects, components of the cement or other cementitious materials are delivered to the site instead of the pre-mixed version. Conventionally, the component delivery truck drives to the site and attempts to deliver the component as close to the mixing site as possible. Unfortunately, this often requires driving over a curb or other surface that is fragile relative to the weight of the delivery truck. For example, to mix stucco on a residential site, a sand truck delivers a pile of sand to the front yard. This may involve driving over a curb, on a sidewalk, on a driveway strong enough only for passenger cars, over the yard that may have a sprinkler system laid, or water control boxes. It would be desirable to have a component delivery system that does not risk damaging fragile surfaces or structures.

The amount of sand or other component delivered is always somewhat more than the actual amount needed, so that dirt from the ground does not accidentally contaminate the sand when scooping the sand to go in the mixer. The result is a left-over pile of sand that needs to be removed from a construction site; this excess sand is wasted. It would be desirable to deliver an amount of a necessary component that more closely approximates the amount actually used in preparing the cementitious material so that less is wasted.

Once the components are delivered, they are mixed with cement, water and other ingredients to form the desired cementitious material. The equipment used to mix the cementitious materials are washed out with water. Because cement water is highly caustic, the washout effluent has to be contained appropriately. One way to handle the waste is to place an empty watertight container on site and permit concrete vehicles to drive up ramps to the container for dumping excess and washout. One such container is described in US Patent Pub 2004/0155126. The empty container is unloaded at the construction site then, when filled with debris and effluent, the container delivery truck has to drive back to the location again, often over relatively fragile surfaces. This method has certain disadvantages, however, such as taking up limited ground space at a construction site and requiring the container delivery truck to drive over relatively fragile surfaces twice. It would be desirable to limit the ground space required for component delivery and waste removal, as well as limiting the need to drive over fragile surfaces and structures.

Therefore, it is an object of this invention to provide a method of using a container for raw components that has a dual purpose of being a washout container. It is a further object to provide a method of delivering, loading, and removing the container from a remote location such that heavy equipment does not have to drive on curbs, driveways, and other prohibited travel areas. A further object is to provide a method for eliminating the excess raw component or slurry that would have been dumped on the ground, minimizing component costs, as well.

SUMMARY OF THE INVENTION

This invention is a method of delivering a necessary amount of a component for a cementitious product to a construction site, depositing the component into a container, using the component to make the cementitious product, and then retaining residual component and material resulting from rinsing the mixing equipment. In its preferred embodiment, an empty plastic container is delivered to the site, the deliverable component is sand, and the cementitious product is stucco. The amount of sand that is needed for stucco is determined and delivered to the plastic container via conveyor belts from sand trucks sitting in the street. The sand is used to mix the stucco in mixers present at the construction site, as known in the art. Once the stucco is mixed, the mixing equipment is rinsed with water and the washout effluent is deposited in the now-empty plastic container. The plastic container is then sealed and picked up with a crane sitting in the street and emptied at an accepted waste facility. Alternatively, the container may be left open for the contents to dry, before it is picked up.

In another preferred embodiment, an empty plastic container is delivered to the site, the deliverable component is sand, and the cementitious product is mortar. The amount of sand that is needed for mortar is determined and delivered to the plastic container via conveyor belts from sand trucks sitting in the street. The sand is used to mix the mortar in mixers present at the construction site and, once the stucco is mixed, the mixing equipment is rinsed with water and the washout effluent is deposited in the now-empty plastic container. The plastic container is then covered and picked up with a crane sitting in the street and emptied at an accepted waste facility. Alternatively, the container may be left open for the contents to dry, before it is picked up.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of the preferred embodiment of the present invention.

FIG. 2 illustrates adding the component of a cementitious material to the empty container from a location remote to the construction site.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 and 2, there is illustrated the inventive method for delivering cementitious materials and waste removal thereof, designated generally as 10, which takes place at construction site 20. The construction site 20 is a general area, such as a city block or parcel of land, wherein a construction, repair, rehabilitation, renovation, or other project requiring a cementitious product is taking place, and includes adjacent roads or channels of ingress and egress where construction equipment, such as delivery vehicles, may be located for utilization at the construction site. The project taking place at the construction site 20 may be characterized as residential, commercial, or industrial; in the preferred embodiment, the project is residential.

The construction site 20 may comprise heavy travel areas, prohibited travel areas, or a combination of both. Heavy travel areas can withstand ingress, egress, and stationary location of heavy construction equipment, such as dump trucks and cranes, without damage to the travel surface or underlying structures. Common heavy travel areas include main or heavy-load-bearing roads, adjacent undeveloped land, and industrial parking lots. Prohibited travel areas are impassable by heavy construction equipment without sustaining damage. Common prohibited travel areas include side streets, driveways, sidewalks, and parking lots that may crack or crumble under excessive weight; street curbs or other embankments; hedgerows; fences; irrigation and wastewater ravines; and residential property which may contain special landscaping or irrigation systems or may collapse under heavy weight, trapping construction equipment or causing damage to underlying pipe systems. In the preferred embodiment, illustrated in FIG. 2, construction site 20 is a residential construction site populated by examples of both heavy travel and prohibited travel areas: main road 25 is a heavy travel area, while residential side-street 24, concrete embankment 23, driveway 22, and yard 21 are prohibited travel areas.

Following the inventive method 10, a container 30 is delivered to the construction site 20. The container 30 may be composed of woven, malleable, or rigid plastic, compacted rubber, metal, or any other material or combination of materials suitable to contain one or more components of a cementitious product. Additionally, the container 30 may be any size large enough to contain the necessary amount of component 31 to complete a project and the amount of waste material generated by rinsing equipment. The container 30 may be shaped like a circle, square, rectangle, or any other shape conducive to containing a cementitious product and waste material. The container 30 may be watertight to contain wastewater. The container 30 may further be closed with a sealing means, such as a cover, lid or hatch to prevent the contents from splashing out. The cover may seal so tightly as to be watertight. In the preferred embodiment, the container is rigid plastic, circular, watertight, large enough to contain sufficient sand to make enough stucco to apply to the exterior walls of a residential structure, and coverable by a custom-fitting removable lid which creates a splash seal.

The container 30 may contain a predetermined necessary amount of a component 31 of a cementitious product, or the container 30 may be empty at delivery. In the preferred embodiment, the container 30 is empty at delivery to facilitate its placement within the construction site 20 at a location conducive to efficiently performing the project. Because this location may be remote from and inaccessible by heavy machinery, the container 30 might be too heavy to place in the location unless it is empty.

The cementitious product contemplated for use in the inventive method may be any cementitious product that is delivered for use in component form and produced immediately prior to its application, such as concrete, plaster, stucco, grout or joint compounds such as spackle and other plastic pastes. The component 31 required to generate the cementitious product is determined by the type of cementitious product to be made, but can be such substances as cement, aggregate, plaster, powderized polymer, or sand. In the preferred embodiment, the target cementitious product is stucco or mortar, and the preferred component is sand.

The component 31 of a cementitious product is delivered to the construction site 20 by a delivery vehicle 40. The delivery vehicle 40 is prohibited from passing over any prohibited travel areas (such as yard 21, driveway 22, concrete embankment 23, and side street 24), so the delivery vehicle 40 advantageously remains on a heavy travel area or other non-prohibited travel area, such as main road 25. Then, an amount of the component 31 of a cementitious product is deposited into container 30 from the delivery vehicle 40 by a conveyor system 50. The conveyor system 50 may be any system suitable to convey the component 31 from the delivery vehicle 40 to the container 30, such as a conveyor belt, paddle-wheel system, or vibrating chute. In the preferred embodiment, the conveyor system 50 is a series of small conveyor belts which convey the component 31 from a dispensing hatch 41 in the delivery vehicle 40, over any prohibited travel areas, to the container 30. Multiple containers 30 may be delivered to the construction site 20, each to contain a different or the same component 31.

In accordance with the inventive method 10, once the container 30 contains the component 31 of a cementitious product, the cementitious product is generated by depositing a desired portion of the component and any other required components into a mix container and mixed until the desired cementitious product is achieved. Preferably the mixer is a portable stucco or cement mixer, but may also be a bucket, tub or other container. In an alternative embodiment, the container 30 itself is used as the mix container. If necessary, other components may be delivered to the container 30 in the same fashion as the described component 31. In the preferred embodiment, the additional components of stucco—usually cement, hydrated lime, and water—are deposited into the container 30 and the contents of the container 30 are mixed with mixing equipment until the desired consistency is achieved. The cementitious product can then be applied as called-for in the project.

Various equipment, such as hand-held mixers, shovels, trowels, putty knives, edgers, darbies, portable mixers with or without chutes, buckets, brooms and towels, may be used to mix and apply the cementitious product. Once the job is completed, any equipment bearing remnants of the cementitious product is washed of the cementitious product, and the effluent—contaminated water, cleaning chemicals, and cementitious refuse—is directed into and stored within the container 30. If the container 30, now containing effluent from the project, is sealable, it can be sealed before removal from the construction site 20. The container 30, if too heavy to be transported on the ground over any prohibited travel areas, is removed from the construction site 20 by crane or over a temporary bridge that will not damage the prohibited travel areas. The container 30 may be taken to a waste facility, emptied and reused. In the preferred embodiment, the waste separated and desirable components, such as aggregate, reclaimed.

While there has been illustrated and described what is at present considered to be the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims. 

1. A method of material handling comprising: a) delivering a container to a construction site; b) adding a component of a cementitious product to the container by conveying the component to the container using a conveyor system; c) making the cementitious product from the component; and d) retaining waste from making the cementitious product in the container.
 2. The method of claim 1 wherein the conveyor system is remote from the container.
 3. The method of claim 1 further comprising removing the container retaining waste from the construction site.
 4. The method of claim 1 further comprising sealing the container substantially closed.
 5. The method of claim 1 wherein making the cementitious product further comprises using a mixer.
 6. The method of claim 4 further comprising rinsing waste from the mixer into the container.
 7. The method of claim 1 wherein the component is sand.
 8. The method of claim 8 wherein the cementitious product is stucco.
 9. The method of claim 1 wherein the container is substantially plastic.
 10. The method of claim 1 wherein the container is substantially watertight.
 11. The method of claim 1 wherein the container further includes a cover.
 12. A method of material handling for a residential construction project on a construction site that includes an area from which heavy equipment travel is prohibited, the method comprising: a) determining the amount of a cementitious component necessary to build the residential construction project; b) delivering an empty container to the construction site; c) adding the determined amount of the component to the container by conveying the component to the container using a conveyor system from outside the prohibited heavy equipment travel area; d) making the cementitious product from the component using a mixer; and e) rinsing waste from the mixer into the container; f) sealing the container substantially closed; and g) removing the container containing waste using a crane from outside the prohibited heavy equipment travel area.
 13. The method of claim 12 further comprising moving the determined amount of the component to a mixer.
 14. The method of claim 12 further comprising emptying the waste from the container.
 15. The method of claim 12 wherein the component is sand.
 16. The method of claim 15 wherein the cementitious product is stucco.
 17. The method of claim 12 wherein the container is substantially plastic.
 18. The method of claim 12 wherein the container further comprises a cover.
 19. The method of claim 12 wherein the container is substantially watertight. 